The Austrian fortress Intra i Sas or lock Valparola was built in the years 1897-1900, the facility, like most from this construction period, was already outdated at the beginning of the war and could not have withstood a direct attack.
The Italians saw things differently, however, and in 1915 the factory was bombarded by heavy artillery from a safe distance and reduced to rubble (the breech was only considered shell-proof up to a caliber of 21 cm). Although the armament, consisting of two 8 cm M 98 cannons, two 6 cm M 98 cannons and four machine guns, had already been removed in good time, the remaining crew was left behind. They resorted to a deceptive maneuver to distract the Italians from the new fortifications on the Hexenstein: they left the lights on at night to pretend to be busy; this confused the Italians so much that they believed until the very end that the plant was still fully operational.
This stratagem was also used successfully in the La Corte lockdown.
In the meantime, rehabilitation measures have been carried out and a museum has been set up in the factory, which can be easily reached from the road on the Valparola Pass.